Abstract Inflammatory bowel disorders can be associated with alterations in gut microbiota (dysbiosis) and behavioral disturbances. In experimental colitis, administration of fish oil (FO) or cannabinoids, such as cannabidiol (CBD), reduce inflammation. We investigated the effect of combined FO/CBD administration on inflammation and dysbiosis in the dextran sulphate sodium (DSS) model of mouse colitis, which also causes behavioral disturbances. Colitis was induced in CD1 mice by 4% w/v DSS in drinking water for five consecutive days followed by normal drinking water. FO (20–75 mg/mouse) was administered once a day starting two days after DSS, whereas CBD (0.3–30 mg/kg), alone or after FO administration, was...